Pathology Research Services Core Shared Resource ABSTRACT Pathology studies at City of Hope Comprehensive Cancer Center (COHCCC) are supported by the Pathology Research Services Core (PRSC), which is composed of three distinct laboratories (Research Histology, Molecular Pathology, and Cytogenetics) and the COHCCC institutional biorepository. The overall goal of the PRSC is to provide COHCCC investigators with access to high quality, timely, and cost-effective pathology services that directly support both animal and human studies, and to provide access to ethically consented and procured human biorepository collections. The biorepository services include patient consenting to COH?s General Research Protocol, thus allowing the PRSC to procure residual solid tissue, additional bone marrow aspirate, and peripheral blood, as well as buccal cells and skin biopsies. With consent in place, biospecimens are ethically procured under the supervision of pathologists, processed, stored, and fully annotated following ISBER Best Practices and NCI Best Practices for Biospecimen Resources. The PRSC is preparing for College of American Pathologists (CAP) Biorepository Accreditation in late 2018. The PRSC also provides expert histopathology (solid and liquid tumors) and molecular and cytogenetics support for translational research by COHCCC investigators. The PRSC, including the institutional biorepository, is overseen by an Internal Advisory Board; the Director, Dennis Weisenburger, MD; and an operations Senior Manager, Karen Miller CLS, MT(ASCP). Oversight is provided by an interdisciplinary faculty Advisory Committee, and user feedback is obtained through an annual survey. The leaders of the laboratories sit on the Advisory Committee and are available for project design and technical consultation as needed. Since the last competing renewal, the PRSC, including the biorepository, was used by 183 unique investigators, 63% (n=116) of whom were CC members and representing all five Programs. The PRSC distributed 794 fresh frozen tissue aliquots, 674 aliquots of serum/plasma/buffy coats, 738 vials of mononuclear cells/peripheral blood mononuclear cells (MNC/PBMCs) (2015-2016 data), and 45,675 formalin-fixed paraffin-embedded (FFPE) sections from clinical and research tissue blocks. The biorepository frozen tissue collection has grown to 20,500 solid tissues (tumor and paired normal tissue when available); 28,360 vials of MNC/PBMCs from bone marrow, peripheral blood, or apheresis products; 50,665 aliquots of serum; 41,620 aliquots of plasma; and 21,500 buffy coats from peripheral blood. The research- only FFPE tissue collection comprises approximately 12,000 blocks.